Automatically compensates for distances up to 35 yards. Pendulum can be locked in place for ground shooting. Extra, extra-long, protected, wrapped fiber. Aperture has a 1.8" inner diameter. Circular field of view. Glow-in-the-dark shooter's ring helps align peep sight. Level with two vertical bars. Level is illuminated by luminescent shooter's ring. Adjustable for left and right handed shooters. Extremely quiet. CNC-machined.